/*
 * Copyright (c) 2010 Stephen A. Pratt
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package org.critterai.math.geom;

/**
 * Indicates the vertex wrap direction of a polygon.
 * <p>Static operations are thread safe.</p>
 */
public enum WrapDirection 
{
    /**
     * Polygon vertex wrap direction is clockwise.
     */
    CLOCKWISE,
    
    /**
     * Polygon vertex wrap direction is counter-clockwise.
     */
    COUNTERCLOCKWISE,
    
    /**
     * The wrap direction hasn't been determined or could not be determined, depending
     * on the use case.
     */
    UNKNOWN;
    
    /**
     * Returns the opposite of the provided direction.
     * NULL and {@link #UNKNOWN} will always return {@link #UNKNOWN}.
     * @param direction The direction to invert.
     * @return The opposite of the provided direction.
     */
    public static WrapDirection getInverted(WrapDirection direction)
    {
        if (direction == CLOCKWISE)
            return COUNTERCLOCKWISE;
        if (direction == COUNTERCLOCKWISE)
            return CLOCKWISE;
        return UNKNOWN;
    }
}
